The use of brake head position devices in the railway industry is well known. They are utilized in the quest to obtain uniform brake shoe wear, which in turn prolongs brake shoe life and offers the economies associated with such a result.
Prior art brake head position devices use a brake head positioning spring consisting of metal friction washers and springs to hold the brake head for even brake shoe clearance upon release of the brake. These prior art designs are a compromise as they are optimized for mid-brake shoe and wheel wear conditions. Use of a prior art brake positioning device can result in the brake shoe touching the wheel tread at either the top or bottom when conditions of no wear or full wear exist among the varying wheel/brake shoe wear parameters. This can result in shoe wear at either the top of bottom of the shoe and require shoe changes before complete shoe wear is accomplished. This shoe wear could adversely affect braking performance due to less shoe surface being applied to the wheel.
Other brake head positioning devices are designed only for a specific adaptability to their respective brake head hanger assemblies.